Your chassis manufacturer manual should have the measurement and how to adjust the ride height for your specific chassis. If you do not have a manual, contact your chassis manufacturer.
Personally, as a customer, I would not do this adjustment. For my chassis, it involves getting under the coach when the coach is loaded and fully aired up for travel. A seperate measurement is taken on the front and rear axle to a point on the frame. There is an adjusting screw that allows the air bags to be filled more or less depending on if the chassis needs to be raised or lowered. When the techs do my annual check, there are always two of them working this at the same time. This may be for safety reasons.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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